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arXiv · 1812.06139

Enhanced Polarization of Low Pressure $^3$He through Metastability-Exchange Optical Pumping at High Field

J. D. Maxwell·J. Alessi·G. Atoian·E. Beebe·C. S. Epstein·R. G. Milner·M. Musgrave·A. Pikin·J. Ritter·A. Zelenski
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Abstract

We report high steady-state nuclear polarization of 1 torr $^3$He gas nuclei via metastability-exchange optical pumping at magnetic fields above 2 T. The introduction of highly polarized $^3$He gas into Brookhaven's Electron Beam Ion Source would enable a new, polarized $^3$He ion source for use at the Relativistic Heavy Ion Collider and a future Electron-Ion Collider facility. By adapting recent developments in high field metastability-exchange optical pumping for higher pressure gas, we have successfully polarized 1 torr $^3$He sealed cells in the EBIS solenoid. Through careful manipulation of the RF discharge parameters, polarizations above 80% were attained at 2, 3 and 4 T, with 89% being reached at 3 T with a 664 s relaxation time.

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J. D. Maxwell, J. Alessi, G. Atoian, E. Beebe, C. S. Epstein, R. G. Milner, M. Musgrave, A. Pikin, J. Ritter, A. Zelenski. 2019-04-11. Enhanced Polarization of Low Pressure $^3$He through Metastability-Exchange Optical Pumping at High Field. https://doi.org/10.1016/j.nima.2019.02.019

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